Evaluation of defect density by top-view large scale AFM on metamorphic structures grown by MOVPE

TL;DR

This paper presents a rapid, AFM-based method for estimating defect density in metamorphic structures, reducing reliance on costly TEM analysis and aiding in process optimization.

Contribution

The paper introduces a novel AFM technique for defect density estimation on non-flat surfaces, enhancing efficiency and cost-effectiveness in evaluating epitaxial structures.

Findings

Successfully applied to structures with defectivity below 10^6

Demonstrated potential for routine quality assessment

Reduced need for transmission electron microscopy analysis

Abstract

We demonstrate an atomic force microscopy based method for estimation of defect density by identification of threading dislocations on a non-flat surface resulting from metamorphic growth. The discussed technique can be applied as an everyday evaluation tool for the quality of epitaxial structures and allow for cost reduction, as it lessens the amount of the transmission electron microscopy analysis required at the early stages of projects. Metamorphic structures with low surface defectivities (below 106) were developed successfully with the application of the technique, proving its usefulness in process optimisation.